I think:

    app.get('/thing', function (req, res) {
      try {
        await user = db.get({user: req.user});
        res.send({user:user});
      } catch {
        res.send(400);
      }
    });

beats the hell out of:

    app.get('/thing', function (req, res) {
      db.get({user: req.user}, function (err, user) {
        if (err) return res.send(400);
        res.send({user:user});
      });
    });

especially when you have conditionals or loops that can look like:

    if (user.name == 'abc') {
      resp = 5;
    } else {
      await resp = db.get_resp({user:user});
    }
    await db.save(something);

I suppose it doesn't get rid of callbacks, just makes them readable.